It is well-known to provide conventional coal-fired power plants in which coal is burnt in a furnace to turn feed-water into steam which is in turn fed to a steam turbine used to drive an electrical generator. Exhaust steam from the turbine is then fed to a condenser where it is cooled and returned to water before being pumped back into the furnace to continue the cycle. The condenser is effective in improving the operating efficiency of the turbine by providing a low pressure environment for the exhaust steam from the turbine.
It is also known to increase the efficiency of such a conventional coal-fired power plant by bleeding partially expanded steam from the turbine to a feed-water heater located between the condenser and the furnace in order to preheat the feed-water into the furnace and improve the operating efficiency. Such arrangements, while generally increasing the overall efficiency of the power plant do reduce the amount of power available from the steam turbine to drive the electrical generator.